Comparative assessment of quality of tilapia (Oreochromis niloticus) and catfish (Clarias gariepinus) stored in ice fish box

Abstract

The quality of two species of fish, (Tilapia) Oreochromis niloticus and (Catfish) Clarias gariepinus stored in the Ice fish box was assessed with fish to ice (1:1, 2:1, 3:1 and 4:1) for 36 and 30 hours respectively. The parameters assessed were: PH, Rigor Index, TVB-N, Sensory Evaluation, Temperature, Relative Humidity and Microbial Analysis. The lowest average temperature and relative humidity for all the treatments were 5.7⁰C and 87.7%, and 5.2⁰C and 93.3% for Tilapia and Catfish respectively. Biochemical analysis revealed pH value for Tilapia decreased significantly (p<0.05) within the storage period for all the treatments. From an initial value of 6.90 to between 6.50-6.80 at the end of storage period (36 hours), for Catfish there was a significant difference (p<0.05) from an initial of 7.1 to 7.6. This increase was steady across all treatment at the end of the storage period (30 hours). The TVB-N value for Tilapia increased significantly within the storage period for all the treatments from an initial value of 5.29mg to 7.22mg, 8.82mg, 12.10mg and 13.28mg respectively for 1:1, 1:2, 1:3, 1:4. Similar trend was reported for catfish from an initial value of 0.98mg to 16.56mg. These values were significantly different (p<0.05).The microbial load did not increase significantly for all the treatment within the storage period. Total Viable Count (TVC) ranged from an initial of 1x10² to 3x10² cfu/g and an initial of 1x10² to 4x10² cfu/g for Tilapia and Catfish respectively. The sensory assessment and organoleptic evaluation of both species were satisfactory at the end of the storage period. However, overall assessment indicates that Tilapia stored longer in the Ice fish box than the Catfish.

Keywords: Organoleptic assessment, Storage, Quality, Fish, Ice